* {
    margin: 0;
    padding: 0;
}

.top {
    height: 50px;
    background-color: rgb(1, 165, 167);
    display: flex;
    justify-content: space-around;
    align-items: center;
}

.top + div:nth-child(2) {
    display: flex;

}

.top > div {
    display: flex;
    align-items: center;
}

.top div {
    margin: 0 10px;
    cursor: pointer;

}

.top > div > div:hover {
    color: blue;
}


.right {
    width: calc(100vw - 200px);
    height: calc(100vh - 50px);
    /*overflow: auto;*/
    /*background-color: #9a6e3a;*/
}

/*----------------------left----------------------------*/
.left {
    width: 200px;
    height: calc(100vh - 50px);
    background-color: #eaffea;
    text-align: center;
}

.left > div {
    cursor: pointer;
    padding: 10px 0;
}

.left > div > div:nth-child(2) {
    text-indent: 2em;
}

.left > div > div:nth-child(1):hover {
    background-color: aquamarine;
}

/*将所有二级菜单关闭*/
.left > div > div:nth-child(2) {
    display: none;
}

/*将第一个二级菜单打开*/
.left > div:nth-child(1) > div:nth-child(2) {
    display: block;
}

.left > div > div:nth-child(2) > div:hover {
    background-color: #0077aa;
}

/*.left > div:hover {*/
/*    background-color: #0077aa;*/
/*}*/